1. Field of the Invention
The present invention is related to a retention device for a boot on a glide board. More specifically, it is related to the field of snowboarding.
2. Description of Background and Relevant Information
In snowboarding, the user's feet are affixed to a board in a position that is substantially transverse with respect to the longitudinal direction of the board. The boots as well as the devices for retaining boots on the glide board must be able to provide adequate comfort to the user, and allow him to steer the board correctly under all circumstances. In order to fulfill these requirements, it is desirable for the boot to be relatively flexible so that the user can walk easily, and so that he/she can bend his/her legs towards the front or to the sides while steering the board, or while executing jumps or figures.
It is also desirable that each retention device allows the user to take rearward support with the lower part of the leg, especially during turns or when the user's back faces a slope.
Prior art documents have suggested retention devices for a flexible boot that allows the user to bend his/her leg towards the front or to the sides, while at the same time providing adequate rearward support.
In particular, the French Patent Publication No. 2746604 discloses a device comprising a base that is extended towards the rear by a portion of the heel support, a dorsal support element being journalled on the heel support portion along an axis contained in the median vertical plane of the base. This device comprises an elastic return means that elastically resists the inclination of the dorsal support element along one of the lateral sides of the device by rotation about the axis when a boot that is retained on the base is tipped.
The device disclosed in French Patent Publication No. 2746604 is very satisfactory in the help that it provides to the user while snowboarding, and is especially satisfactory in terms of safety.
However, this device does not allow the dorsal support element to perfectly follow the movements of the lower part of the user's leg, especially in the direction of a lateral inclination, because the structure of the ankle journal induces complex movements of the bone which are different from a simple rotation about an axis.
As a result, the dorsal support element rubs against the boot or the lower part of the user's leg, thereby hindering the steering.
In addition, this device is relatively complex and expensive to manufacture.